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lattice-boltzmann.com/content/1-dimensionless-lbm.md

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 is the Knudsen number.
 
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+As for the Navier-Stokes equations we see that the non-dimensional BGK equation is parametrized
+with an unique transport coefficient which is the Knudsen number. In the next episodes of this series
+we will make the link between the BGK and the Navier--Stokes equations and show how we discretize
+the BGK equation in order to simulate weakly compressible fluid flows.